Improved propeller



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UNITED STATES PATENT OFFICE.

CHARLES OHARA, OF LONDON, ENGLAND.

IMPROVED PROPELLER.

Specification forming part of Letters Patent No. 35,035, dated April 2.2, 1862.

To @ZZ wiz/0m 'it may concern.-

Be it known that I, CHARLES OIIARA, of et Upper Seymour' Street, lVest, London, in the United Kingdom of Great Britain and Ireland, have invented a new and Improved Propeller for Boats, Ships, and other Vessels; and I do hereby declare that the following is a full, clear, and exact description of the same, reference being had to the accompanying drawings, making part of this specification, in which- Figure l is a stern view of a vessel having my propeller applied; Fig. 2, a central vertical section of the after part of the vessel and the propeller; Fig. i3, a plan corresponding with Fig. 2; Fig. 4, a horizontal section of the same, and Fig. 5 a perspective view showing the propeller in an inverted position.

Similar letters of reference indicate corresponding parts in the several figures.

This propeller is more especially adapted to the navigation of canals and other shallow waters, and therefore I have represented in the drawings its application to a iiat-bottomed vessel suit-able to that kind of navigation. It may be made of wood or iron; but I propose generally to make it of iron, and hollow; and it .may be arranged with its axis either in a vertical position, as shown in the drawings, o1I in a horizontal position.' I propose generally to arrange it in a semieircular recess, a c., Figs. 2 and 1l, formed for its reception in the stern of the vessel; but two such propellers may he arranged, one on each side of the vessel.

The general forni of the propeller is semicylindrical; but I prefer that the surface l) b, which impinges upon the water, instead of being made a plane surface, should be corrugated parallel with the axis, as represented; and I also prefer in the vertically-arranged propeller to continue its Vupper horizontal surface, as shown at c c, to make it form a complete circle, such continuation consist-ing of a mere plate. The shaft d of this propeller, which is concentric with its arc-formed surface e, extends right through it, and the lower end of said shaft is fitted to a suitable bearing ina portion of the framing of the vessel, and the upper portion thereof extends upward into the interior of the vessel for the connection of the engine'by which the driving power is applied to the propeller, the manner of application of such power being such as to give the propeller an oscillating movement about its axis, and so cause each half of its impinging surface l) b to strike the water alternately, the half on one side of the axis striking the water while the half on the other side returns to its initial or starting point, and the curved seinicircular surface e preventing any reaction.

The method which I propose to adopt for applying the power is illustrated in Figs. l, 2, and 3, and vmay be described as follows: The upper part of the shaft d has secured to it a toothed wheel, I, and has fitted loosely to it, above this wheel, an arm, f, to which is fitted and attached a slide, g, furnished with a tooth, g', which works through a slot, f in the arin f, and which can be brought into any one of the spaces between the teeth of the wheel e, and so made to connect the arm with the shaft in such manner that by the connection of the piston-rod or connectingrod of a reciprocating engine with the said arm the said arm may be made to work the propeller.

7L is a lever working on a fixed fulcrum, vi, and entering between twofpins, g2 g3, on the slide g, to work the said slide, and j is a notched post for the reception of the said 1ever to lock the slide and arm. By reversing the position of the arin fupon the propellershaft the impinginv surface b b of the propeller may be turned in front, and the propeller so be made to back t-he vessel; or by shifting the said arm a less distance the propeller may be made to act sidewise upon the vessel to turn it in a very small circle.

Then this kind of propeller is placed with its axis in. a horizontal position, only the lower half should be submerged, and two propellers having their actions alternating with each other should be used.

That I claim as my invention, and desire to secure by Letters Patent, is-

l. The arrangement and Operation 0f the of the ereulzyr plate c, as herein shown and semi-eylndre oscillating propeller Within the described. l

concave a a, substantially as herein shown CHARLES OI-IARA. and described. Witnesses:

2. Having lche radial face of the said pro- ARCHIBALD MURRAY, j peller provided with eorrugetons b, as shown 59 Chancery Lane, Solicor. and described. W. J. GADSDEN, v- 3. The Combination, with the said propeller, His Clerk. f4 

